This core will provide state of the art proteomic and mass spectrometry support for all projects (J. Zheng, H. Gendelman, and Y. Persidsky) in this proposal. This will include protein profiling for neuronal progenitor cells, monocyte-derived macrophages, microglia as well as cell-cell interactions relevant to studies that affect virus and cell-protein changes in brain mononuclear cell inflammatory responses and for developmental therapeutics in NeuroAIDS. We will use 2-dimensional electrophoresis (2DE) with Difference Gel Electrophoresis (DICE) (2DE DICE) as a primary profiling approach. To complement these established methods, we will use an ABI4800 MALDI-TOF/TOF (Applied Biosystems, Inc.) for rapid and precise mass analysis. Post-translational modifications such as phospnorylation will be done with a QQ-LIT (QTrap4000, Applied Biosystems, Inc.). In addition, we have quantitative mass spectrometry systems that incorporates isotope-coded affinity tags (ICAT), isotope Tags for Relative and Absolute Quantification (iTRAQ), and Stable Isotope-labeling with Amino Acids in Cell culture (SILAC) for protein labeling or tagging. Our ongoing collaborations with Beckman-Coulter, Inc. have extended our protein capabilities with the acquisition of a Proteomel_abPF2D Protein Fractionation System for the profiling complex protein samples. Taken together, this core has evolved from simple surface enhanced laser desorption ionization assays included in the initial program project proposal to become a university-wide well-integrated core facility, which serves to greatly facilitate all the proposed research included in the application.